Mesa, Arizona (CNN) - In a whispering campaign not ready to go public, some senior Republicans are so anxious about the state of the GOP race they are actually considering the unheard of: a scenario that would lead to another candidate entering the Republican primary race, and potentially an open convention.

They are not unhappy enough, however, to go on the record calling for another candidate to enter the fray. In fact, when pressed, many Republicans say the chatter about another candidate is inevitable in this long and inconclusive primary process. They also say it's just not likely to happen.

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Why?

"If you bring somebody new into the race, that person will lose," said a senior GOP strategist who admits a bias towards Romney. "The party - especially conservatives - will not respond to somebody who has not gone through the process."

That being said, it's clear Rick Santorum's recent rise in the polls - and what some see as his electability problems - has struck a nerve with Republicans.

"There is something called agenda control," said one unaffiliated GOP strategist. "Santorum does not have it. Instead of talking about the economy, he's been going down rabbit holes for the last four or five days."

Santorum's emphasis on cultural issues may intensify his conservative and evangelical support and help him win the nomination or at least differentiate himself from Newt Gingrich. The fear is he may also be narrowing his support in a general election population.

And Santorum's surging candidacy is not the only concern for senior Republicans. Mitt Romney's inability to close the deal has also raised eyebrows - and angst. And the anxiety will only intensify should Romney lose his home state of Michigan in the primary on February 28, several senior Republicans told CNN.

"Michigan is the whole shooting match," said one senior GOP strategist not aligned with a campaign. Says another: "If Romney loses Michigan, all hell breaks loose."

Given that real possibility, one knowledgeable GOP source confirms that some Republicans are circulating the deadlines and the basic math that would allow another candidate to get into the nomination fight and take it all the way to the convention. More than a half dozen states' filing deadlines have yet to pass. A majority of the delegates to the national convention are still up for grabs. One more factor to be considered: many states are choosing their delegates proportionally, which makes it easier for a candidate pick up delegates without outright winning a state.

Politico first reported the existence of a document circulating among Republicans.

Santorum's highlighting of cultural issues could play well for him in the short-term. But the worry among Republicans is that his views will raise the question of his electability. "After a while, Republican voters will start asking whether this is the guy to take on Obama," says one GOP strategist. In addition to the fear of a potential loss to Obama, some Republicans worry about losing the House of Representatives if Santorum were at the top of the ticket.

“There is no faith he would bring independent or moderate voters. If he does well on Super Tuesday you’ll have serious people talking about convention strategies etc,” one Republican congressional leadership aide told CNN Senior Congressional Correspondent Dana Bash.

"Santorum would so alienate voters, especially women…he would be lucky to carry a dozen states," one senior Republican told CNN, referring to Santorum's disapproval of pre-natal screening.

Santorum's campaign disagrees. It considers him a strong social conservative who is the best equipped to take on President Obama on the economic issues – -particularly in the rustbelt states. "He won in Pennsylvania, which has both Democrats and women the last time I checked," says a senior Santorum adviser, who calls his boss a "full spectrum conservative."

One of the Republicans who has seen the memo said "no one is hoping that this will come to play," regarding a new candidate entering the fray. Yet some Republican partisans feel they need to make some contingency plans depending on the outcome in coming primaries. Other veteran Republicans contacted by CNN dismissed any possibility of another candidate entering the contest at this date.

There are no names of possible candidates mentioned in the memo. Who would the Republicans possibly turn to? The usual suspects include Sarah Palin, Indiana Gov. Mitch Daniels, New Jersey Gov. Chris Christie or Former Florida Gov. Jeb Bush. They could still enter the race although they all have repeatedly said they will not mount a campaign despite new inquiries by some in the party.

"I really would not be interested," Daniels told CNN affiliate WISH Monday. "If we get to that point, I would be interested in finding someone who can present a really credible and winning alternative to where the nation is going right now. I still think it's very unlikely. These things have a way of resolving themselves."

For its part the Republican National Committee is downplaying the prospects of another contender entering the fray.

“We are four games into what is a 54 game league and people are trying to pick the equivalent of a super bowl or a world series. We have 4 great candidates. I’m confident one of them will be our nominee and will go on to be successful in November,” RNC Spokesman Sean Spicer said.

We are witnessing the final collapse of the Great Obstruction Party. It started with the 'self-rightious majority', followed by 'reagan-nomics' (trickle down only works if you stand up from the toilet too soon), then 'Moron George' deregulated us into the great recession, and now the Tea Party has given us these four clowns, that even they don't want.

Obama 2012

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February 21, 2012 08:37 am at 8:37 am |

JuanVonDinklus

I still haven't heard these candidates really talk about what they will do that will help. They throw out slogans and bash everyone on the other side, but that seems to be all they are good at doing. Santorum is running for the office of Pope. Romney is running for office of US Venture Capitol to add to his millions. Gingrich, doesn't know what he is running for and the media and establishment are afraid of Ron Paul. So that's all there is to choose from. Maybe we should nominate a one celled protozoa and just give it unlimited advertising and cue cards to follow. Let's see if that wins. If not, we can always try something else.

February 21, 2012 08:38 am at 8:38 am |

unhanon

It would be really interesting if someone could do a compare-and-contrast between the current Republican primary process, and the 2008 Democratic primary which had two contenders going neck-and-neck right down to the wire. Yet I don't recall anyone talking seriously about the possibility of either Clinton or Obama running as a 3rd party candidate, or the possibility of "party bigwigs" bringing in a new candidate at the last minute. What is making for some of these differences?

February 21, 2012 08:40 am at 8:40 am |

Boo

These idiots are so desperate to win the presidency it's laughable. They know they're in trouble and that all of their candidates are pathetic. When there is a party whose only goal is to defeat Obama, they deserve to lose. They don't give a damn about the American people. I am enjoying their implosion and desperation.

February 21, 2012 08:40 am at 8:40 am |

mike

The last thing we need is another clown getting on the Republican bus.

February 21, 2012 08:41 am at 8:41 am |

Ari

As a libertarian leaning independent voter neither Romeny nor Santorum would get my vote. I'm hoping the GOP does follow through on plan B. I'd like to see someone electable in the race.

February 21, 2012 08:41 am at 8:41 am |

indie voter

Registered independents can not vote in primaries, that is a whole lot of people (40% of the population). A fanatic such as Rick will never pass muster with independents who are fiscally responsible, socially smart and will never stand for the reversal of women's rights to the 50s or religion as the reason to elect a president.

February 21, 2012 08:42 am at 8:42 am |

Taioseach

It's becoming more and more evident that the GOP isn't overly concerned with the 2012 elections. When they are defeated it will be more of the same obstructionist game playing, IF, the manage to remain in the majority after mid-terms.

Hopefully the great unwashed will finally wake up and realize that they do not have their best interest at heart.

February 21, 2012 08:42 am at 8:42 am |

Tad

I have never voted anything but Republican, but IF Santorum were the pick, I would vote for Obama...he is the worst of the worst. I would love a do over, but could live with Romney...and I am conservative about economic issues, but liberal about social issues, so he plays better to me and what I want from a leader.
Problem with Republicans is that they would cut off their noses to please their faces...do we want to win the big prize or just fight for the opportunity to run? I live in VA where Republicans hold the legislature, the senate the governorship and they are making so many mistakes...and dealing only with social issues that in 10 years will be meaningless and not dealing with our economic issues and come next election...many will be gone and democrats will control both houses. Remember Barry Goldwater and 1964...we are about to repeat.

February 21, 2012 08:42 am at 8:42 am |

Marti58

None of the Republican candidates can ever measure up to President Obama's intelligence, integrity, leadership etc. President Obama represents the majority of the American people. He understands us and kept his words and promises. I appreciate him even more now, after his 3 years in the White House. A president to be proud of. Thank you

February 21, 2012 08:42 am at 8:42 am |

Malcolmscott

The GOP brought this on themselves. They feed the hate and venom that the "Tea Party" people were spewing during the '08 campaign and now they are unable to control it. They desevre all of this. I hope it leads to Santorum getting the nomination. With him at the top of the ticket GOP voter turn out will be low and the Dems may be able to take back the congress and we can actually get something done. No more party of "No".
They have been waiting out his presidency since the day he took office. Doing nothing that may give him even the slightest bit of a win. So I hope they pay dearly for all thety "have"n't done.

February 21, 2012 08:43 am at 8:43 am |

JSallee

So according the elites (the GOP-establishment) if you don't vote OUR way (srewey RINO like Romney); we'll force another RINO on you. "Your votes don't count". This truely is turining into a Bananna Republic!

February 21, 2012 08:44 am at 8:44 am |

Win Adams

In 2008 I voted against McCain and hoped that the 2012 election would be different. However, it now looks like I will be voting against again. Mr. Santorum's view of birth control and abortion will guarantee that I will not vote for him. I would never vote for Newt, to much baggage. I might have considered Romney, just not sure. I probably would have voted for Christy, but won't get the chance. Surely, the Republican party can do better than this.